A conventional printed circuit board inspection apparatus comprises an upper inspection jig and a lower inspection jig. The lower inspection jig has guide posts and a circuit board to be inspected is located on the guide posts. The lower inspection jig is positioned by a lifting device in one and an opposite direction toward and away from the upper jig. The upper inspection jig has an X-Y-.O slashed. drive device, and may include a universal jig, and a rubber jig. The X-Y-.O slashed. drive device changes the relative horizontal positions of the upper and lower inspection jigs in accordance with the following method.
A pattern film used when a circuit board was manufactured is adhered temporarily to a rubber jig by an operator. A double coated adhesive tape is adhered to the surface of the inspected circuit board and the lifting device moves the lower inspection jig upwardly toward the upper jig to adhere the pattern film to the circuit board to be inspected. The operator observes any misalignment between the pattern film and the printed board, and then employs the X-Y-.O slashed. drive device to fine-adjust the horizontal position of the upper inspection jig as required to correct the misalignment.
The foregoing operation is repeated in a trial-and-error fashion to determine relative positions of the upper and lower inspection jigs. Positioning is made in the abutting state, i.e., under the same conditions as those where the conductivity of the circuit board is inspected. This method, however, is complicated, time consuming and tedious.
To avoid this complication, it is possible to adjust the position of the upper inspection jig with the aid of a camera inserted and removed from between the jigs of the apparatus. This method, however, requires that fine positioning be made with the upper and the lower jigs separated from each other, resulting in misalignment when they are engaged.
One object of the present invention is to provide a printed circuit board inspection apparatus which can simply and accurately position an upper inspection jig.
Another object of the present invention is to provide a printed circuit board inspection apparatus in which the relative positions of an upper jig and a printed circuit board on a lower jig can be measured with the circuit board in contact with the upper jig.